robertson



J. T. ROBERTSON. Tritur'ating Mill.

No. 230,660. Patented Aug 3,1880% ilal )7/ TIVESS N. PETERS, FHOTO-LITHOGRAPHER, WASHINGTON. D16,

UNrrED STATES JUDAH T. ROBERTSON, OF NEYV YORK, N. Y.

TRlTURATlNG-MILL.

SPECIFICATION forming part of Letters Patent No. 230,660, dated August 3, 1880.

Application filed October 16, 1879.

To all whom it may concern:

Be it known that I, J UDAH TOURO Bonner- SON, of New York, in the county and State of "ow York, have invented a new and useful ln'iprovement in Pulverizers or Triturating- Mills, of which the following is a specification.

My invention relates to machinery for reducin g minerals and other material to a finelydivided condition, in which the material is inclosed in a revolving cylinder and subjected to the grinding and triturating action of a number of balls.

The object of my invention is to effect the grinding more rapidly than is usual by acting upon a smaller portion of the material at a time, and to render efficient the action of an atmospheric current to charge and discharge the mill.

To this end my invention consists of a cylinder separated into a series of sections with openings in the division-plates, whichareso arranged that the blast of a blower will draw or force the material through or among the balls before it can be discharged from the mill. By this means a blast may be used to afford a continuous action of the machine without losing time to fill and empty the mill, and the material will be removed as fast as it becomes sufficiently pulverized, without remaining in the mill to absorb the power in unnecessary grinding and to impede the reduction of that part of the material that requires to be further operated upon. The draft of air not only keeps the mill cool and prevents the injury by discoloration or otherwise of those kinds of material that are injured by heat, but the current also tends to keep clean the surfaces of the balls and the linings of the cylinder, so that they will remain in the most efficient condition for performing their work.

To enable others skilled in the arts to which it appertains to make and use my invention, I will proceed to describe its construction and operation with reference to the drawings.

Figure 1 is a side elevation of the mill, showing the cylinder a a a and the spur-wheel b, by which it is revolved on its hollow journals, and the blower c and the valve (1, by which the suction is regulated. Fig. 2 is a transverse section of the cylinder, in which supportingrollers are indicated by dotted lines under the flanges and Fig. 8 is alongitudinal section of one end of the same, both figures being on an enlarged scale, and showing theporcelain lining and wood backing with which such cylinders are usually made.

The ends of the cylinder and the partitions between the sections are fitted with plates at the line of the axis, which are perforated with small holes. If the ballsf filled the cylinder, the grinding action would be imperfect, and if they did not cover the holes the material would beliable to pass through unground with the draft. It is therefore better that they should cover the holes without filling the sections. The ground or crushed material to be triturated is carried with the current through the open journal at one end, by means of a hopper or other suitable arrangement, into the first section, where it is subjected to the action of the balls, and itis then carriedinto the middle section, and then into the last section at the other end, whence itpasses through the blower and is delivered by a spout into a suitable receptacle.

The rapidity of the passage of the material through the mill is dependent upon the blower, the action of which is also regulated by the valve placed between it and the cylinder. In their passage through the sections the finest particles most readily pass above the balls between the division-plates and escape with the least action, while the larger particles remain among the balls and receive the grinding they require, and the repetition of the operation through the several sections insures the perfect trituration of the whole.

The drawings represent the revolving cylinder divided in three sections; but it may be made with more sections, if desirable, and it would also answer a useful purpose in some cases if it were made with but one chamber and supplied with balls that covered the escape-openin g continuously, and thus admitted of operation with a blower, in the manner herein described. In a similar manner, although the cylinder is represented horizontal, it may be placed in an inclined position with the escape covered with balls, to insure the grinding of thematerial'thatis admitted at the end above them.

Fine wire screens may be placed over the rated plates are used they should be made of as thin metal as practicable, and the holes should be countersunk on the discharge side.

Having thus described a mill made with my improvements, I claim as myinvention and desire to secure by Letters Patent The triturating-cyliiuler having hollow journals and made in sections aa, separated by division-plates having central perforations, c, said perforations being covered by balls f, in combination with blower a, substantially as described.

J. TOURO ROBERTSON.

YVitnesses:

WALTER PELL, Wu. KEMBLE HALL. 

